Method and apparatus for wireless power transmission with harmonic noise cancellation

Abstract

A wireless power transmission apparatus includes a source resonator configured to transmit an output power from which a harmonic component has been cancelled to a wireless power reception apparatus by resonating with a target resonator of the wireless power transmission apparatus, and a resonant power generator configured to differentially input a first input signal and a second input signal to the source resonator, and cancel the harmonic component of the output power.

What is claimed is: 
     
       1. A wireless power transmission apparatus comprising:
 a source resonator configured to transmit an output power to a wireless power reception apparatus by resonating with a target resonator of the wireless power reception apparatus, wherein the transmitted output power has a predetermined frequency band; and 
 a resonant power generator comprising first and second notch filters coupled to a low-pass filter (LPF), 
 wherein the first and second notch filters are configured to cancel a third harmonic component of the output power, and the LPF is configured to cancel a fifth or higher odd-order harmonic component of the output power, 
 wherein the resonant power generator is configured to differentially input a first input signal and a second input signal to the source resonator, and cancel an even-order harmonic component of the output power, and 
 wherein the source resonator is further configured to transmit the output power from which the third harmonic component and the fifth or higher odd-order harmonic component have been cancelled to the wireless power reception apparatus. 
 
     
     
       2. The apparatus of  claim 1 , wherein the resonant power generator comprises:
 a first power amplifier configured to generate the first input signal; and 
 a second power amplifier configured to generate the second input signal. 
 
     
     
       3. The apparatus of  claim 2 , wherein the resonant power generator further comprises:
 a first driving circuit coupled to the first power amplifier; and 
 a second driving circuit coupled to the second power amplifier. 
 
     
     
       4. The apparatus of  claim 3 , wherein the first driving circuit and the second driving circuit are configured to generate a 180 degree phase difference between the first input signal and the second input signal. 
     
     
       5. The apparatus of  claim 2 , wherein the first power amplifier comprises the first notch filter;
 the second power amplifier comprises the second notch filter; and 
 the resonant power generator is further configured to cancel the third harmonic component of the output power using the first notch filter and the second notch filter. 
 
     
     
       6. The apparatus of  claim 5 , wherein the first notch filter and the second notch filter are configured to match an output impedance of the wireless power transmission apparatus to an input impedance of the wireless power reception apparatus. 
     
     
       7. The apparatus of  claim 5 , wherein the LPF coupled to the first and second notch filters of the resonant power generator is further coupled to the source resonator. 
     
     
       8. The apparatus of  claim 2 , wherein the first power amplifier and the second power amplifier are Class-E amplifiers. 
     
     
       9. The apparatus of  claim 1 , wherein the source resonator is further configured to receive the first input signal and the second input signal via a differential input port comprising a separate grounding unit. 
     
     
       10. The apparatus of  claim 1 , wherein the predetermined frequency band is 6.78 MHz. 
     
     
       11. The apparatus of  claim 1 , wherein the predetermined frequency band is tens of Hz. 
     
     
       12. A wireless power transmission apparatus comprising:
 a source resonator configured to transmit an output power to a wireless power reception apparatus by resonating with a target resonator of the wireless power reception apparatus; 
 a resonant power generator comprising:
 a first power amplifier comprising a first notch filter and configured to generate a first input signal; and 
 a second power amplifier comprising a second notch filter and configured to generate a second input signal; 
 wherein the resonant power generator is configured to cancel an even-order harmonic component of the output power by differentially inputting the first input signal and the second input signal to the source resonator, and cancel a third harmonic component of the output power using the first notch filter and the second notch filter; and 
 
 a low-pass filter (LPF) coupled to the first and second notch filters and configured to cancel a fifth or higher odd-order harmonic component of the output power; 
 wherein the source resonator is further configured to transmit, to the wireless power reception apparatus, the output power from which the even-order harmonic component, the third harmonic component, and the fifth or higher odd-order harmonic component have been cancelled. 
 
     
     
       13. A wireless power transmission method in a wireless power transmission apparatus, the method comprising:
 generating, via a resonant power generator, a first input signal and a second input signal; 
 differentially inputting, via the resonant power generator, the first input signal and the second input signal to a source resonator and cancelling an even-order harmonic component of the output power; 
 cancelling, via a low-pass filter (LPF) and first and second notch filters coupled to the LPF, a harmonic component comprising a third harmonic component and a fifth or higher odd-order harmonic component of an output power of the source resonator; and 
 transmitting, via the source resonator, the output power from which the harmonic component including the third harmonic component and the fifth or higher odd-order harmonic component has been cancelled to a wireless power reception apparatus by resonating with a target resonator of the wireless power reception apparatus. 
 
     
     
       14. The method of  claim 13 , wherein the cancelling of the harmonic component of the output power comprises:
 generating the first input signal using a first power amplifier; and 
 generating the second input signal using a second power amplifier. 
 
     
     
       15. The method of  claim 14 , wherein the cancelling of the harmonic component of the output power further comprises generating a 180 degree phase difference between the first input signal and the second input signal using a first driving circuit coupled to the first power amplifier and a second driving circuit coupled to the second power amplifier. 
     
     
       16. The method of  claim 14 , wherein the first power amplifier comprises a first notch filter;
 the second power amplifier comprises a second notch filter; and 
 the cancelling of the harmonic component of the output power further comprises cancelling the third harmonic component of the output power using the first notch filter and the second notch filter. 
 
     
     
       17. The method of  claim 16 , wherein the first notch filter and the second notch filter are configured to match an output impedance of the wireless power transmission apparatus to an input impedance of the wireless power reception apparatus. 
     
     
       18. The method of  claim 16 , wherein the LPF is further coupled to the source resonator. 
     
     
       19. A non-transitory computer-readable storage medium storing instructions for controlling a computer to perform the method of  claim 13 .